Exploring and enhancing the accuracy of interior-scaled Perdew-Zunger self-interaction correction

Abstract

The Perdew-Zunger self-interaction correction(PZ-SIC) improves the performance of density functional approximations(DFAs) for the properties that involve significant self-interaction error(SIE), as in stretched bond situations, but overcorrects for equilibrium properties where SIE is insignificant. This overcorrection is often reduced by LSIC, local scaling of the PZ-SIC to the local spin density approximation(LSDA). Here we propose a new scaling factor to use in an LSIC-like approach that satisfies an additional important constraint: the correct coefficient of atomic number Z in the asymptotic expansion of the exchange-correlation(xc) energy for atoms. LSIC and LSIC+ are scaled by functions of the iso-orbital indicator zσ, which distinguishes one-electron regions from many-electron regions. LSIC+ applied to LSDA works better for many equilibrium properties than LSDA-LSIC and the Perdew, Burke, and Ernzerhof(PBE) generalized gradient approximation(GGA), and almost as well as the strongly constrained and appropriately normed(SCAN) meta-GGA. LSDA-LSIC and LSDA-LSIC+, however, both fail to predict interaction energies involving weaker bonds, in sharp contrast to their earlier successes. It is found that more than one set of localized SIC orbitals can yield a nearly degenerate energetic description of the same multiple covalent bond, suggesting that a consistent chemical interpretation of the localized orbitals requires a new way to choose their Fermi orbital descriptors. To make a locally scaled-down SIC to functionals beyond LSDA requires a gauge transformation of the functional's energy density. The resulting SCAN-sdSIC, evaluated on SCAN-SIC total and localized orbital densities, leads to an acceptable description of many equilibrium properties including the dissociation energies of weak bonds.

12 pages, 8 figures

References in corpus (8)

• Fermi Orbital Derivatives in Self-Interaction Corrected Density Functional Theory: Applications to Closed Shell Atoms
• A step in the direction of resolving the paradox of Perdew-Zunger self-interaction correction
• Stretched or noded orbital densities and self-interaction correction in density functional theory
• First-principles study of mechanical and electronic properties of bent monolayer transition metal dichalcogenides
• Perdew-Zunger self-interaction correction: How wrong for uniform densities and large-Z atoms?
• A Step in the Direction of Resolving the Paradox of Perdew-Zunger Self-interaction Correction. II. Gauge Consistency of the Energy Density at Three Levels of Approximation
• Improvements in the orbitalwise scaling down of Perdew-Zunger self-interaction correction in many-electron regions
• Local self-interaction correction method with a simple scaling factor

Cited by in corpus (5)

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• Study of Self-Interaction Errors in Density Functional Calculations of Magnetic Exchange Coupling Constants Using Three Self-Interaction Correction Methods
• One-electron self-interaction error and its relationship to geometry and higher orbital occupation
• Spherical vs. Non-Spherical and Symmetry-Preserving vs. Symmetry-Breaking Densities of Open-Shell Atoms in Density Functional Theory